A proposal is made for the training of a physician in molecular genetics. This proposal will prepare the applicant as a productive, independent researcher in the molecular aspects of human genetics. The means for the development as a researcher in a supportive, stimulating environment at the University of Pennsylvania in the Department of Human Genetics is proposed. The research undertaken in this proposal will be directed towards the understanding of transcriptional control of gene expression by investigating the transcription of the human ribosomal genes. The expression of the ribosomal genes is integral to cell growth and development, and is altered in a wide variety of physiologic and pathologic conditions. Understanding the transcription of the ribosomal genes will provide a basis in understanding the alterations in gene expression in cancer, senescence, growth and differentiation. The applicant is a pediatric geneticist who will have the opportunity for training in the basic sciences under the guidance of a molecular geneticist. The applicant's progress will be reviewed, and guidance provided by a Human Genetics Faculty Committee. The committee will review the applicant's training, recommend further training, and judge the completion of Phase I of the proposal. Completion of that phase, as judged by the committee, will initiate Phase II and independent biological experiments. The committee will regularly review that work to its completion and meet with the applicant on a formal and informal level.